Solution or bath for use in electrically preparing stencil-plates, die-plates, and the like



G. E. WERTHEINIER.

SOLUTION'OR BATH FOR USE IN ELECTRICALLY PREPARING STENCIL PLATES, DIE

PLATES, AND THE LIKE.

APPLICATION man MAY 16. |918.

1,376,369. Patented Apr. 26, 1921.

Ammamum Chloride (lfdzyvzd) 200,115

S14/ve nto@ G, E. Werh@ mer.

UNITED STATES PATENT OFFICE.

GOTTHOLD E. WERTHEIMER, OF ASTORIA, NEW YORK.

SOLUTION OR BATH FOR USE IN ELECTRICALLY PREPARING STENCIL-PLATES, DIE-PLATES, AND THE lLIKE.

Application filed Hay 16,

To all whom t may concern:

Be it known that I, Go'r'rHoLoVErHRAIM VERTHEIMER, subject of' the'Emperor of Austria, and a declarant of the United States of America,having applied for first papers in March, 1917, residing at 531 Firstavenue, Astoria, borough of'Queens, in the county of Queens and State ofNew York, have invented certain new and useful Improved Solutions orBaths for Use in Electrically VPreparing Stencil-Plates, Die-Plates, and

the like, of which the following is a specification. v

This invention relates t0 a composition of matter adapted to be used asthe solution or bath in connection with a process of preparing metallicstencil plates or die plates or blocks or like articles, involving theerosionl or Veating away of certain parts of such plates by the use ofelectric current in conjunction with said solution or bath.

The object of the present invention is to provide a solution or bathwhich will enable said process to be expeditiously applied to annealedor hardened metals, such as steel, whereby stencil or die plates orblocks formed of such annealed or hardened metals may be rapidlyproduced at a low cost and with a minimum of'labor.

Another object of the invention is to provide a solution or bath by theuse of which the metal from the plate or block ma be rapidly removedwhile producing a uni orm and smooth surface on the remainingpor tion ofthe plate or block.

The improved solution or bath according to the present inventioncomprises a mixture of sulfuric and nitric acids and water, with smallproportions of iodin, copper nitrate and acetic acid. These ingredientsare preferably employed in the proportions of eighty parts of sulfuricyacid, twenty parts of nitric acid, two parts of iodin, five parts ofcopper nitrate, two parts of acetic acid, and eight hundred and ninetyone parts of water. -The various ingredients are mixed together andthoroughly stirred to secure an intimate admixture and the resultingsolution is then preferably heated to a temperaf ture of approximatelyeighty-three degrees Fahrenheit, and maintained at about thattemperature during-the operation of the process, byany suitableelectrical or other means. The solution may, of course, vbe

Specification of Letters Patent.

Patented Apr. 26, 1921.

191s. serial No. 235,014.

.parts of the plate or block unprotected by a resisting coating ofsuitable form are very rapidly eroded or cut away. In tests which havebeen made with this solution heated to the temperature above mentionedand usin lan electric current of about 6 or 7 volts an about 35 to 40amperes, it has been found possible to cut into annealed or hardenedsteel to a depth of one millimeter in six hours over any desiredconfiguration. The great utility of this solution or bath for thepurpose stated will thus be readily recognized.

The accompanying drawing diagrammatically indicates the manner in whichthe solution may be used in the treatment of a metallic plate or blockfrom which a stencil plate or die plate is to be prepared.

I have found that the addition to the other ingredients of the solutionor bath, of copper nitrate, iodin, and acetic acid in small proportions,tends to reduce the erratic action of thesolution on the metal and toincrease the uniformity and smoothness of the surfaces produced thereon.

I have also found that the addition to the solution or bath of ammoniumchlorid considerably reduces the time necessaryto cut to a particulardepth in, or remove a certain amount of metal from, a metallic plate orblock, and in the majority of cases its use will be commercially andpractically desirable for this reason. I preferably use two hundredparts of ammonium chlorid, with the amount of water in the solutioncorrespondingly reduced, and the other ingredients in the proportionsstated above. In preparing the solution with the ammonium chloridtherein, granulated ammonium chlorid is firstly dissolved in water, atapproximately the boiling point in substanf tially the proportion of onepound of ammonium chlorid to one gallon of water. By this means asaturated solution of ammonium chlorid is obtained. The otheringredients are mixed together in substantially the proportions stated,and the solution of ammonium chlorid prepared as described, insubstantially the proportion given above is added thereto, the entiremixture being thoroughly stirred to secure an intimate admixture of thevarious ingredients. This solution also is preferably used heated to atemperature of approximately eighty-three degrees Fahrenheit.

With such solution it has been found possible to cut to a depth of threesixty-fourths of an inch in one hour, in annealed or hardened steel.

The solution herein described is particularly intended for use in.connection with the process described in my companion application SerialNo. 208558, filed December What I claim and desirel to secure by LettersPatent is l. A solution for use in the electrolytic` treatment ofmetallic plates or blocks, prepared by mixing together sulfuric acid,nitric acid and water, and small proportions of iodin, copper nitrateand acetic acid.

2. A solution lfor use in the electrolytic treatment of metallioplatesor blocks, prepared by mixing together the following ingredients insubstantially the following proportions, namely, sulfuric acid eightyparts,

nitric acid twenty parts, iodin two parts, Y

copper nitrate five parts, acetic acid two parts, and water eighthundred and ninety one parts.

3. A solution for use in the electrolytic treatment of metallic platesor blocks, prepared by mixing together sulfuric acid, nitric acid,ammonium chlorid and water, and small proportions of iodin, coppernitrate and acetic acid.

4. Asolution for use in the electrolytic treatment of metallic plates orblocks, prepared by mixing together the following ingredients insubstantially the following proportions, namely, sulfuric acid eightyparts, nitric acid twenty parts, ammonium chlorid two hundred 7parts,iodin two parts, copper nitrate five parts, acetic acid two parts, andwater six hundred and ninety one parts.

5. A solution for use in the electrolytic treatment of metallic platesor blocks, prepared by mixing together sulfuric acid, nitric acid andwater, and small proportions of iodin, copper nitrate and acetic acid,

' heated to a temperature of about eighty three degrees Fahrenheit.

In testimon whereof I aliix m si ature.

GOTTIIOLD E. WERT EI ER.

